Folding box



ct. 3l, 1939. A, BENNETT 2,177,856

- FOLDING Box Filed June 2, 1957 w wwwwww INVENTOR.

A R THU/ BEN/VE r T f ATTORNEY.

Patented oct. 31, 193e UNI-TED STA-.TES

PATENT oFFicE 2 Claims.

This invention relates to folding cardboard or paper boxes and cartons which are formed of cut-out and/or scored blanks', and the object of the invention is to provide means for more quickly and conveniently setting up such blanks to box form and securely hold them erected. Other advantages of the invention will appear from the following description and accompanying drawing.

In the drawing: Figure 1 is a plan view of a cut-out folding box blank in process of being set up, and fully erected at the right-hand end.

Figure 2 is a perspective view of a portion of a non-cut out, but simply creased and scored box blank in process of being set up.

Figure 3 is a plan view of the right-hand corner of the ilat blank of the box of Figure 2.

Figure 4 is a plan view of a scored and cornercut box'blankshowing in dotted lines the set-up position.

Before describing the drawing in detail. it may be stated that folding boxes and cartons have heretofore been died out or'cut out in avariety of forms and scored along certain lines and/or creased so as to be easily folded to box form. Some of the forms adopted have interlocking tongues or apsat the corners while others leave simple flaps or scored margins which are brought `together to form the standing sides or wallsof the box, and are thereafter glued together, or

sometimes stapled. My improvement avoids the j ordinary gluing or stapling of the corners or flaps tri hold the box erected, or the use of interlocking tongues, yet makes a very strong joint andis :performed in a'fraction of the time heretofore required.

The improvement consists in applying to cer-Q tain portions of the iiaps or overlying portionsof the box blanka coating of normally senil-tacky compound such as partially oxidized latex, which though` not sticky enough to ladhere to plain paper, cardboard, Wood, glass or metal, will nevertheless adhere tenaciously to a similar coating adhering to itself when in the dry film state, if pressed together. This property, however, is not permanent, butin the course of a week or two gradually diminishes upon aging or exposure to air. Upon experiment,I discovered several means 5 of prolonging this property by using various yagents which seem to form a slight protective film over the'latex layer, probably due to their beingl miscible with latex in the liquid phase but insoluble in the coagulated form, such as glycerin, glycols or glycol phthalate.

On further experiment, I found that a partially oxidized latex formed by treatment in the liquid phase had a greater tendency to stick to itself whendry by simple pressure, plus thcfadvantage of. retaining this property for a relatively long period of time, at least for six months under ordinary conditions. The partial oxidation of the latex also produced a product which could be used more sparingly than the unoxidized due to the fact 'that it possessed greater cohesive Rubber latex, 33% solution gallon s 50 Hydrogen peroxide, 20%A by volume gallon`s v3 Cobalt nitrates. pounds 3% Add the peroxide and cobalt nitrate to latex and stir in suitable mixer that is heated with servatives to prevent coagulation before using.)

, To apply this adhesive to the flaps of the cartons or lfolding box blanks, any ofthe conventional means may be employed such as brushing, gumming with commercial gummers or4 spreading, and spread the Work out to dry spontaneously` before stacking, or dry by passing through a drier 1 in warm air.

From the above it Will be noted that if the folding boxes were to be erected Within a few days or a week, a plain latex coating could be used, but for regular trade a six months or more life would be required. If the coated work is stored :in a ceci piace protested trein' the cir- Vculation of air, the effective life of the coating will be much extended.

In the drawing three common forms of folding box blanks are shown, that of Figure 1, that of Figures 2 and 3, and that of Figu're 4, all coated at certain places with the semi-tacky compound described.

In Figure 1 the blank has a bottom I, sides 2, ends 3, flaps Il extending beyond the side walls, and flaps 5 extending beyond the end walls. All walls and flaps are defined by suitable score marks 6 to facilitate bending along that line in setting up the box to form the vertical walls as shown at the right-hand end of the View.

The semi-tacky coating is shown at 'I on the upper faces of flaps and 5, so that when the side walls are erected to the Vertical as at 2 and the side flaps 4 folded to position of 4', wall 3 may be folded upward to lie against the outer sides of flaps 4, and ap 5 may then be bent over and down inside the box as shown at 5' to embrace both flaps 4 between 3 and 5 and bring the coated face of 5 into direct contact with the coated faces of 4, and whereupon a slight pressing f the folded members together` instantly causes the two contacting coated surfaces to rmly adhere to one another so that they cannot be again separated without tearing the carton or box material.

The box corner of Figure 4 will be next described as it is simplest, consisting, in the blank form shown, of a bottom wall 8, side wall 9 with end flap I0 and end wall II, all scored as at 6 as described for Figure 1. In this case, the upper face of end wall II is coated with the semitacky layer at T and the under side only of flap I0 is similarly coated, so that when wall 9 is erected to the vertical position 9 and flap I0 swung inward to position I0 its coated face will be in confronting relation to coated area 'I of wall II as the latter is bent up to vertical position and will instantly lock therewith as the two coated surfaces are pressed together.

Figure 2 is a perspective view of a folding box blank having in the flat condition the scoring shown at 6 and 6 in Figure 3 and wherein the bottom of the box is designated I2, the side wall 43, end wall I4, end flap I and corner flaps I5, I1 and I8.

As the blank of Figure 3 is scored only but not cut at the corners, its method of folding, while common in the art, is not so simple as that of Figures 1 and 4, though easily understood by reference'to the perspective View, Figure 2, wherein the left-hand corner is shown completely erected, and the members and score lines of the partially folded right-hand corner willeasily be located by the same numerals as used in Fig-4 ure 3)/ From Figures 2 and 3 it will be seen that with this form of blank the semi-tacky coating 1 need only be applied to the upper surface of end walls and flaps I 4 and I5 as these come face to face when the box is erected as indicated in Figure 2. The semi-tacky coating I may extend across the upper faces of corner fold portions or iiaps I6, II and I8, as I6 and I1 also come face to face with I5 and I4, and will make the extreme cortact.

ners a trifle atter, though it makes handling of the blank a bit more convenient if the coating is omitted from the corners.

By the improvement described, it provides a pile of fiat blanks which will not stick together, yet are instantly ready for erecting into box form in a moments time without use of glue, water or other solvent, or waiting for the ordinary glues and pastes to stick and dry, and also dispenses with the troublesome work of inserting flaps into slots as required for the interlocking flap type of folding boxes, yet provides a folding box which when erected in a moments time is firmer than other types and resists unfolding even to destruction of the stock.

In my experiments I have found that the addition of the cobalt salt to natural, concentrated or partially oxidized latex tend to control the rate and degree of oxidation to such an extent as to cause the latex to possess far greater properties of adhesion to its own dried lms. Moreover, films of latex, so treated with cobalt nitrate, maintain this adhesive property for prolonged periods of time while latex films, not so treated, have a tendency to resinify-on exposure to air and lose this property of being able to adhere together upon contact. Normal or natural latex loses this property of being self sensitive in about two weeks on exposure; partially oxidized latex loses it in about two months; but my tests indicate that cobalt treated latex retains this property for periods upwards of six months. This improved treatment has valuable commercial usage in that boxes or cartons gummed with cobalt treated latex do not lose their adhesive properties and became useless when stored for future use. l I

Having thus described my invention and the manner of its use, what I claim is:

l. In a folding paper box or carton, the improvement which consists in providing those faces of the corners and walls of the blank which come face to face when the blank is erected to box form with a coating of semi-tacky adhesive containing rubber latex and cobalt nitrate, the degree of adheslveness of the dried coating being insuicient to cause the blanks to stick together when piled in superimposed relation with coated surfaces against uncoated surfaces, but sufficient to cause immediate and substantially inseparable cohesion of the coated faces when simply pressed together in face contact.

2. In afolding paper box or carton, the improvement which consists in providing those faces of the corners and walls of the blank which come face to face when the blank is erected to box form with a coating of.'semitacky adhesive containing partially oxidized rubber latex and cobalt nitrate, the degree of adhesiveness'of the dried coating being insufficient to cause the blanks to stick together when piled in superimposed relation with coated surfaces against uncoated surfaces, but sufficient to cause immediate and substantially inseparable cohesion of the 'coated faces when simply pressed together in face con- ARTHUR BENNETT. 

